<template>
  <div class="drawer">
    <div :class="maskClass" @click="closeByMask"></div>
    <div :class="mainClass" :style="mainStyle" class="main">
      <div class="drawer-head">
        <h4>{{ title }}</h4>
        <span class="close-btn" v-show="closable" @click="closeByButton">X</span>
      </div>
      <div class="drawer-body">
        <slot />
      </div>
    </div>
  </div>
</template>
<script>
export default {
  props: {
    // 是否打开
    display: {
      type: Boolean
    },

    // 标题
    title: {
      type: String,
      default: '标题'
    },

    // 是否显示关闭按钮
    closable: {
      type: Boolean,
      default: true
    },

    // 是否显示遮罩
    mask: {
      type: Boolean,
      default: true
    },

    // 是否点击遮罩关闭
    maskClosable: {
      type: Boolean,
      default: true
    },

    // 宽度
    width: {
      type: String,
      default: '400px'
    },

    // 是否在父级元素中打开
    inner: {
      type: Boolean,
      default: false
    }
  },
  computed: {
    maskClass: function () {
      return {
        'mask-show': (this.mask && this.display),
        'mask-hide': !(this.mask && this.display),
        'inner': this.inner
      }
    },
    mainClass: function () {
      return {
        'main-show': this.display,
        'main-hide': !this.display,
        'inner': this.inner
      }
    },
    mainStyle: function () {
      return {
        width: this.width,
        right: this.display ? '0' : `-${this.width}`,
        borderLeft: this.mask ? 'none' : '1px solid #eee'
      }
    }
  },
  mounted() {
    if (this.inner) {
      let box = this.$el.parentNode
      box.style.position = 'relative'
    }
  },
  methods: {
    closeByMask() {
      this.maskClosable && this.$emit('update:display', false)
    },
    closeByButton() {
      this.$emit('update:display', false)
    }
  }
}
</script>
<style scoped>
/* 遮罩 */
.mask-show {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 999999;
  background-color: rgba(0, 0, 0, .5);
  opacity: 1;
  transition: opacity .5s;
}

.mask-hide {
  opacity: 0;
  transition: opacity .5s;
}

/* 滑块 */
.main {
  position: fixed;
  z-index: 999999;
  top: 0;
  height: 100%;
  background: #fff;
  transition: all 0.5s;
  overflow-y: auto;
  max-width: 448px;
}

.main-show {
  opacity: 1;
}

.main-hide {
  opacity: 0;
}

/* 某个元素内部显示 */
.inner {
  position: absolute;
}

/* 其他样式 */
.drawer-head {
  display: flex;
  justify-content: space-between;
  height: 1.5rem;
  line-height: 1.5rem;
  padding: 0 0.3rem;
  font-size: 0.7rem;
  font-weight: bold;
  border-bottom: 1px solid #eee;
}

.drawer-body {
  font-size: 0.7rem;
  padding: 0.3rem;
}

.close-btn {
  /* position: absolute;
    height: 44px;
    width: 44px;
    right: 6.25%;
    top: 50%;
    bottom: auto; */
  display: inline-block;
  cursor: pointer;
  height: 100%;
  padding-left: 20px;
  font-size: 0.6rem;
  -webkit-transform: translateY(0%);
  -moz-transform: translateY(0%);
  -ms-transform: translateY(0%);
  -o-transform: translateY(0%);
  transform: translateY(0%);
  overflow: hidden;
  text-indent: 100%;
  white-space: nowrap;
  -webkit-transition: opacity .2s;
  -moz-transition: opacity .2s;
  transition: opacity .2s
}

.close-btn::after,
.close-btn::before {
  content: '';
  position: absolute;
  height: 3px;
  width: 32px;
  left: 50%;
  top: 50%;
  background-color: #5c4b51;
  -webkit-backface-visibility: hidden;
  backface-visibility: hidden
}

.close-btn::after {
  -webkit-transform: translateX(-50%) translateY(-50%) rotate(45deg);
  -moz-transform: translateX(-50%) translateY(-50%) rotate(45deg);
  -ms-transform: translateX(-50%) translateY(-50%) rotate(45deg);
  -o-transform: translateX(-50%) translateY(-50%) rotate(45deg);
  transform: translateX(-50%) translateY(-50%) rotate(45deg)
}

.close-btn::before {
  -webkit-transform: translateX(-50%) translateY(-50%) rotate(-45deg);
  -moz-transform: translateX(-50%) translateY(-50%) rotate(-45deg);
  -ms-transform: translateX(-50%) translateY(-50%) rotate(-45deg);
  -o-transform: translateX(-50%) translateY(-50%) rotate(-45deg);
  transform: translateX(-50%) translateY(-50%) rotate(-45deg)
}

@media only screen and (min-width:640px) {
  .drawer-head {
    display: flex;
    justify-content: space-between;
    height: 0.6rem;
    line-height: 0.6rem;
    padding: 0 0.1rem;
    font-size: 0.2rem;
    font-weight: bold;
    border-bottom: 1px solid #eee;
  }
}
</style>